Preparation and characterization of tunable oil-encapsulated alginate microfibers

Abstract

A single-step microfluidic approach was developed which allowed a wide range of oil-loaded calcium-alginate microfibers to be fabricated at the same compositions but with different morphologies. A framework for characterization of wavy fibers was developed which linked the fiber morphology and tensile strength to the encapsulation type and geometry. The geometry of oil encapsulates as well as the fibers surface morphology were conveniently tuned via the gelation reaction dynamics and phase flow rates. A 2D mathematical reconstruction of the fiber's surface revealed that fibers having spherical and ellipsoid encapsulates enjoyed the highest surface roughness. Tubular fibers endured the highest tensile force before failure, compared to fibers with other encapsulate geometries at a fixed alginate phase ratio (ϕ alg). Fibers with increased ϕ alg withstood a higher tensile force. However, the strength of fibers reduced if the increase in ϕ alg altered the encapsulate geometry from tubular to discrete oil segments. Tubular fibers also underwent maximum elastic and plastic deformation prior to failure, among all fibers.

Influence of Rhamnolipids and Ionic Cross-Linking Conditions on the Mechanical Properties of Alginate Hydrogels as a Model Bacterial Biofilm

“…The degree of cross-linking of the polymer strongly influences the water absorption ability and the mechanical properties of the hydrogel [6]. Cross-linked alginate hydrogels find numerous applications in many fields, including waste removal agents [8,9], drug carriers [10,11], controlled drug release systems [12][13][14][15], wound dressing materials [16][17][18][19], food products [20,21], and tissue engineering [22][23][24]. Due to their high affinity for water and mechanical properties similar to soft tissue, they are also used as a material for the construction of scaffolds supporting and facilitating cell growth, multiplication, and differentiation [25].…”

A novel capsule-based smell test fabricated via coaxial dripping

“…Past works have presented various techniques to fabricate oil-encapsulated alginate capsules with spherical or tubular shape, including microfluidics, jet-cutting, vibrating jet, spray-drying, coextrusion dripping, dispersion [16,17]. Some of these techniques have been characterized, such as the coaxialjetting used to fabricate oil-encapsulated alginate microfibers [17], but others such as coextrusion dripping lack such characterization hindering their capability to produce controlled capsules. To our knowledge, the use of oil-containing alginate capsules has never been previously used to test olfaction.…”